#include <iostream>
#include<string>
#include<sys/socket.h>
#include<cstring>
#include<sys/types.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<stdlib.h>

void Usage(std::string proc)
{
    std::cout<<"Usage \n\t"<<proc<<"local_ip local_port"<<std::endl;
}


int main(int argc,char* argv[])
{
   if(argc != 3)
    {
        Usage(argv[0]);
        exit(1);
    }
    std::string serverip = argv[1];
    uint16_t serverport = std::stoi(argv[2]);

    //1.创建套接字
    int sockfd = socket(AF_INET,SOCK_DGRAM,0);
    if(sockfd < 0)
    {
        std::cerr<<"socket error ... "<<std::endl;
    }
    //2.client要不要bind？要不要显示的bind？
    
    struct sockaddr_in server;
    memset(&server,0,sizeof(server));
    server.sin_family = AF_INET;
    server.sin_port = htons(serverport);
    server.sin_addr.s_addr = inet_addr(serverip.c_str());

    std::string message;
    while(true)
    {
        std::cout<<"Pleasure Enter#";
        std::getline(std::cin,message);
        sendto(sockfd,message.c_str(),message.size(),0,(struct sockaddr*)&server,sizeof(server));

        struct sockaddr_in peer;
        socklen_t len = sizeof(peer);
        char buffer[1024];
        ssize_t n = recvfrom(sockfd,buffer,sizeof(buffer)-1,0,(struct sockaddr*)&peer,&len);
        if(n>0)
        {
            buffer[n] = 0;
            std::cout<<"server echo# "<<buffer<<std::endl;
        }
    }

    return 0;
}